The anti-inflammatory effects of asiatic acid in lipopolysaccharide-stimulated human corneal epithelial cells

AIM： To investigate the anti-inflammatory effects of asiatic acid（AA） on lipopolysaccharide（LPS）-induced inflammatory response in human corneal epithelial cells（HCECs）.METHODS： Cell viability was measured using a cell counting kit-8（CCK-8） assay.Quantitative real-time polymerase chain reaction（qR T-PCR） was used to determine the mR NA expression of interleukin-8（IL-8）,interleukin-6（IL-6）,interleukin-1β（IL-1β）,tumor necrosis factor-alpha（TNF-α）,and transforming growth factor-β（TGF-β） in HCECs.Intracellular reactive oxygen species（ROS） was measured using the ROS assay kit.Glutathione（GSH） concentration was measured using the total GSH assay kit.Akt1 and Akt phosphorylation（p-Akt1） levels were measured by Western blotting and immunofluorescence.RESULTS： AA induced toxicity at high concentrations and significantly stimulated the proliferation of HCECs at concentrations of 20 μmol/L for 1h.LPS at concentrations of 300 ng/mL for 1h significantly stimulated the mR NA expression of IL-8,IL-6,IL-1β,TNF-α,and TGF-β in HCECs,while the stimulation effects were significantly inhibited by AA（20 μmol/L）.In addition,AA was found to decrease the content of ROS,increase GSH generation,and also inhibit LPS-induced p-Akt in HCECs.CONCLUSION： AA decreases the generation of inflammatory factors IL-8,IL-6,IL-1β,TNF-α,and TGF-β in LPSstimulated HCECs.AA significantly inhibites the intracellular concentrations of ROS and increases GSH generation.AA also inhibites LPS-induced p-Akt in HCECs.These findings reveal that AA has anti-inflammation effects in LPS-stimulated HCECs.

Asiatic acid-pectin hydrogel matrix patch transdermal delivery system influences parasitaemia suppression and inflammation reduction in P. berghei murine malaria infected Sprague-Dawley rats

Objective: To report the influence of transdermal delivery of asiatic acid(AA) in Plasmodium berghei-infected Sprague Dawley rats on physicochemical changes, %parasitaemia and associated pathophysiology. Methods: A topical once-off AA(5, 10, and 20 mg/kg)- or chloroquine(CHQ)-pectin patch was applied on the shaven dorsal neck region of Plasmodium berghei-infected Sprague Dawley rats(90-120 g) on day 7 after infection. Eating and drinking habits, weight changes, malaria effects and %parasitaemia were compared among animal groups over 21 d. Results: AA-pectin patch application preserved food and water intake together with %weight gain. All animals developed stable parasitaemia(15%-20%) by day 7. AA doses suppressed parasitaemia significantly. AA 5 mg/kg patch was most effective. AA and CHQ displayed bimodal time-spaced peaks. CHQ patch had a longer time course to clear parasitaemia. Conclusions: AA influences bio-physicochemical changes and parasitaemia suppression in dose dependent manner. In comparison by dose administered, AA has much better efficacy than CHQ. AA may be a useful antimalarial. AA and CHQ displays bimodal peaks suggesting possible synergism if used in combination therapy.

The recovery and protective effects of asiatic acid on differentiated human neuroblastoma SH-SY5Y cells cytotoxic-induced by cholesterol

Objective:To investigate the effect of asiatic acid(AA) on the differentiated human neuroblastoma SH-SY5 Y cells cytotoxic-induced by cholesterol.Methods:Human neuroblastoma SH-SY5 Y cells were either exposed to different concentrations of AA or treated with different doses of cholesterol to reveal their responding viability by MTT assay.The selective 1 mmol/L concentration of AA was then used to test for either the protective or the recovery effects on the cells treated with 250 mmol/L concentration of cholesterol.Results:AA has a propensity to directly increase the viability of differentiated human neuroblastoma SH-SY5 Y cells.Cholesterol has significant cytotoxic effect on those cells in a concentration-dependent manner.AA has the ability to slightly recover the viability of the differentiated culture cytotoxic-induced by cholesterol but could not protect those cells from cytotoxic-induced by cholesterol.Conclusions:High concentrations of cholesterol were observed to be harmful to the neurons and AA had a slight effect of reducing neuronal death caused by cholesterol.

Asiatic acid inhibits lung cancer cell growth in vitro and in vivo by destroying mitochondria

Asiatic acid(AA), a pentacyclic triterpene found in Centella asiatica, displays significant antiproliferative effects on cancer cells in vitro although the underlying mechanism of this effect remains unknown. This study investigated the efficacy and mechanism of action of AA against lung cancer both in vivo and in vitro. Using the MTT assay, AA was found to induce apoptosis in a dose- and timedependent manner, an effect enhanced by pretreatment with an autophagy inhibitor. It also elevated expression of microtubule-associated protein 1 light chain 3(LC3) and decreased the expression of p62.Furthermore, exposure to AA resulted in collapse of the mitochondrial membrane potential and generation of reactive oxygen species(ROS), suggesting mitochondria are the target of AA. In the mouse lung cancer xenograft model, oral administration of AA significantly inhibited tumor volume and weight accompanied by significant apoptosis of lung cancer cells. In addition, it led to a significant decrease in the expression of proliferating cell nuclear antigen(PCNA). In summary, the results show that AA significantly reduces lung cancer cell growth both in vitro and in vivo and that the associated apoptosis is mediated through mitochondrial damage.

Asiatic acid mitigates hyperglycemia and reduces islet fibrosis in Goto-Kakizaki rat,a spontaneous type 2 diabetic animal model

The Goto-Kakizaki(GK) rat is a spontaneous type 2 diabetic animal model,which is characterized by a progressive loss of beta islet cells with fibrosis.In the present study,the hypoglycemic effect of asiatic acid(AA) in GK rats was examined.GK rats receiving AA at a daily dose of 25 mg·kg-1 for four weeks showed a significant reduction in blood glucose levels.Age-matched normal Wistar rats were given 0.5% sodium carboxymethyl cellulose(CMC-Na) solution for the same periods and used as control.Compared to the normal Wistar rats,GK rats treated with AA showed improvement in insulin resistance partially through decreasing glucose level(P < 0.01) and insulin level(P < 0.05).Furthermore,the results of immunohistochemistry indicate that AA treatment reduced islet fibrosis in GK rats.Fibronectin,a key protein related to islet fibrosis,was over-expressed in GK rats,which was reversed significantly by AA treatment(P < 0.05).These findings suggest that AA has a beneficial effect on lowering blood glucose levels in GK rats and improves fibrosis of islets in diabetes,which may play a role in the prevention of islets

Spectroscopic Studies on the Interaction of Asiatic Acid with Bovine Serum Albumin

Fluorescence spectroscopy, Fourier transform infrared （FT-IR） spectroscopy, circular dichroism （CD） and FT-Raman spectroscopy were employed to analyze the binding of the asiatic acid （AA） to bovine serum albumin （BSA） under simulative physiological conditions. Fluorescence data revealed that the fluorescence quenching of BSA by AA was the result of the formation of BSA-AA complex. The fluorescence quenching mechanism of BSA by AA was a static quenching procedure. According to the Van＇t Hoff equation, the thermodynamic parameters enthalpy change （△H0） and entropy change （△S0） for the reaction were evaluated to be --12.55 kJ·mol^-1 and 67.08 kJomol 1, respectively, indicating that hydrophobic and electrostatic interactions played a major role in stabilizing the complex. The influence of AA on the conformation of BSA has also been analyzed on the basis of FT-IR, CD and FT-Raman spectra.

Chinese herb microneedle patch for wound healing

Traditional Chinese medicine and Chinese herbs have a demonstrated value for disease therapy and sub-health improvement.Attempts in this area tend to develop new forms to make their applications more convenient and wider.Here,we propose a novel Chinese herb microneedle(CHMN)patch by integrating the herbal extracts,Premna microphylla and Centella asiatica,with microstructure of microneedle for wound healing.Such path is composed of sap extracted from the herbal leaves via traditional kneading method and solidified by plant ash derived from the brine induced process of tofu in a well-designed mold.Because the leaves of the Premna microphylla are rich in pectin and various amino acids,the CHMN could be imparted with medicinal efficacy of heat clearing,detoxicating,detumescence and hemostatic.Besides,with the excellent pharmaceutical activity of Asiatic acid extracted from Centella asiatica,the CHMN is potential in promoting relevant growth factor genes expression in fibroblasts and showing excellent performance in anti-oxidant,anti-inflammatory and anti-bacterial activity.Taking advantages of these pure herbal compositions,we have demonstrated that the derived CHMN was with dramatical achievement in anti-bacteria,inhibiting inflammatory,collagen deposition,angiogenesis and tissue reconstruction during the wound closure.These results indicate that the integration of traditional Chinese herbs with progressive technologies will facilitate the development and promotion of traditional Chinese medicine in modern society.